부산대학교 도서관

Physical optics models were developed for scattering of HF radiation by irregular terrain when an antenna is located on or near the scattering surface. The primary interest was in skywave radiation patterns for communication links using the ionosphere. Second-order reflections were included in the solution through an image approximation, and the UTD result for an impedance half-plane was used to reduce reflections due to truncating the current distribution on the surface. Arbitrary 2-D or 3-D terrain profiles can be entered into the codes, and the source can be an antenna with currents generated by the NEC method of-moments code or a point source. Results are validated by comparing with 2-D integral equation solutions for actual terrain contours.